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ERDC/CRREL TR-02-1
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SAMPLING
The accurate chemical characterization of any contaminated site requires the
development and implementation of a comprehensive plan outlining several
possible sampling strategies. First, the area of interest must be delineated; this
may be an entire site or several defined areas within a site. Then appropriate
sampling strategies must be selected for that area. The distribution of contami-
nants is generally site-specific and will depend upon several factors, including
the manner in which the contamination occurred, the physical and chemical
properties of the contaminant involved, soil type, the geology, and the hydro-
geology of the site.
Safety Procedures
Sampling of potentially EM-contaminated soil should only occur after
appropriate safety level clearance of the sampling site. High explosives such as
RDX, HMX, and TNT have chemical, physical, and toxicological properties
different from common environmental contaminants. The potential for an explo-
sion in particular mandates that a very high level of diligence and care be taken
with the design and implementation of the health and safety protocols. Exposure
of high explosives to heat, shock, impact, friction, and electrostatic charge can
lead to violent reactions including detonation, deflagration, and burning or high-
rate decomposition. Moreover, care must also be taken to avoid ingestion or
inhalation of explosive particles or vapors, because they are toxic to humans.
Special safety procedures have therefore been developed for explosives sampling
at contaminated sites. As a final consideration, many military ranges may also
contain a significant amount of unexploded ordnance on the surface or buried in
the soil. This unique and important risk and its proper management are discussed
in Appendix A.
Most firing ranges cover large areas, making a comprehensive soil survey of
the site an extremely costly and time-consuming exercise. An alternative
approach is to start with a hydrogeological study. Screening of the groundwater
provides an initial estimate of the extent of site contamination, since it indicates
whether explosives and explosive metabolites have leached into the water table.
Groundwater samples are obtained using wells, which should be installed under
the supervision of a hydrogeologist. However, no wells should be drilled without
proper clearance and specific precautions (level 3 clearance is recommended, see
Appendix A). Groundwater screening should be accompanied by a preliminary
random survey of composite soil samples. If traces of explosives are detected in
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